delete (别名) from tblA (别名) left join tblb (别名) on。。。用法
1、创建使用的表及数据
CREATE TABLEYSHA ( code VARCHAR(10), NAME VARCHAR(20) ) CREATE TABLEYSHB ( code VARCHAR(10), col VARCHAR(10) ) INSERT INTO YSHA VALUES (1,'A1') INSERT INTO YSHA VALUES (2,'A2') INSERT INTO YSHB VALUES(1,'Row1') INSERT INTO YSHB VALUES(1,'Row2') INSERT INTO YSHB VALUES(1,'Row3') INSERT INTO YSHB VALUES(3,'Row1')
2、delete from left join
DELETE A FROM YSHA A LEFT JOIN YSHB B ON A.code=b.code WHERE b.code is NULL SELECT * FROMYSHA SELECT * FROM YSHB
DELETE FROM YSHA WHERE NOT EXISTS(SELECT 1 FROM YSHB B WHERE YSHA.code=b.code ) SELECT * FROMYSHA SELECT * FROM YSHB